Crawler Loader/Dozer Common Faults

Case 1450BTIP – Most Case crawlers have transmission pressure gauges – this is a valuable tool for diagnosing faults. If yours is broken, think about getting it replaced.


Q: When cold, why does my transmission not engage drive straight away?
A: Often this is due to a lack of pressure due to the transmission pump sucking air – cavitating.
Low oil level?
Check hose clamps on all suction lines
If any oil leaks are present, while machine is parked – these are usually leaks on the suction side of system & need repair.
If all clamps are tight & no leaks are present – the problem could be the charge pump itself.

Q: Why is my transmission overheating?
A: Caused by a number of reasons
1) Air flow through radiator / oil cooler restricted with dirt, grass etc.(usually effects engine temp as well)
2) Loss of oil flow due to bad pump or internal leakage at torque convertor or transmission clutch packs
3) Transmission oil being superheated by faulty clutch pack operation. eg – two being engaged at the same time (fwd & rev / low & hi on same side)

Q: Why won’t my machine engage left & right tracks at the same time?
Why is there a hesitation when I change gears/range?
A: There is a problem with internal oil leakage on the slower side. Often oil control rings on shafts are at fault. Sometimes faulty seal rings at clutch pack piston seals.

Q: Why does one track want to drive even when in neutral?
A : There is a broken plate in a clutch pack, locking it up & causing it to permanently drive.

Q: My machine has lost all drive & hydraulics!
A : Flexplate likely is broken – check inside engine bellhousing for debris.

Q: What do I look for when buying a used dozer / loader?
A: All of the above!
Get the machine to operating temperature; at an idle check each individual gear; the transmission pressure & response time should be EXACTLY the same for each selection.

If you need any other question answered regarding your CASE Crawler Loader Dozer please leave a comment in the box at the bottom of the page & I’ll get back to you ASAP.

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179 thoughts on “Crawler Loader/Dozer Common Faults

  • I have a 1960ish Case 850 straight that I was working when I heard a rumbling mechnical noise under the seat. I immediately backed the unit out of the work area and noticed a loss of power to the right tracks. It still operates but not as before so I have left it parted until I can get an idea of what might be the problem. Any insight would be very helpful. Thanks!!

    • Hello Randy,
      My first thoughts are that a bearing has failed & this could affect gear contact & the drive performance. I would suggest you drain the transmission oil & see if there is any sign of metal contamination in the oil.
      You should also inspect the transmission suction screen as this will also show any sign of metal failure.
      If it looks ok in the transmission, drain the RH final drive & see what you find…..
      Don’t use the machine till you find the cause of the noise – as this can cause further damage & repair cost.
      Regards alrman

  • I have a 1985 Case 450c. My transmission is making a loud banging noise. I can feel the vibrations on the main forward reverse shaft when the machine is running. Would bent or broken clutch disks be a culprit? As soon as the machine is pushing a load it will run silent. I have drained the oil and no contamination. machine functions as it should. The same noise is made in forward and reverse gears. The machine sat for a couple years prior to me buying it. It seems to make a milder noise while in neutral and then intensify when engaged. Any help would be appreciated. Nobody locally seems to know anything about these machines.

    • Hello Austin,
      Usually, bent or broken clutch plates will not cause any noises as you have described.
      When you drained the oil did you look at the suction screen? This will tell you if something is failing in the transmission. Also, did you drain the two final drive oils, it is possible something could be wrong there.
      It is also possible you have worn out engine mountings, or worn driveshaft universals.


  • My blade drops sometimes.. It runs fine… Then all of sudden it loses pressure and falls down. No leak and tank is full??

    • Hello Matias,
      Thank you for your visit! 🙂

      I assume you have a dozer?
      Is this a Case Machine?
      What model is it?
      If the blade is 2 feet off the ground, how long does it take to reach the ground?

      • Old 60’s something dozer starts up runs fine can track forward and back but can’t turn just one track

        • Hey Marcus,

          ……just how old do you think I am?!
          Mate, without knowing make or model I can’t tell you anything too specific.
          I would say you need to start by testing pressures & see if there are any differences between LH & RH tracks.
          Drain oil & see if any trash in oil & pickup/suction screens & transmission filter as well.
          Do the brakes still work on this machine? Do they feel normal?

          Hope this helps a little

  • I have a 455C Case Loader and when operating after 15 to 20 minutes the transmission pressure builds up so high that it blew the filter and the filter housing apart. After fixing it back, I put a inline pressure gage on the filter assembly and then within 10 to 15 minutes it blew the “O” ring out of the filter and the pressure raised over 500psi.
    Is there anyway you can help and tell me what you think the problem may be?

    • Hi Chuck,
      I would first look at the relief valves located under the torque convertor housing. It is possible the one or more of the valves is sticking, causing the high pressure.
      The plungers/valve pistons should move freely in their bores.
      Cheers 🙂

  • My 1995 Case 850E Dozer’s Hydraulic control stopped working suddenly while I was logging on a steep slope, fluid was low however I filled it to the full mark the control still did nothing. The single lever control feels like it’s connected, is there an in-line control valve that could be disconnected? I don’t have a repair or maintenance manual.
    Thank you,

    • Hi Steve,
      Can you confirm your problem is simply hydraulic control (blade lift & angle), or loss of drive as the transmission also uses a single lever.

      • Everything else works properly, the control “T” handle and all connections to the valve unit are connected, however there is no response from any input from the handle. I have backed the machine off the hillside and it is sitting level, there are no leaks or signs of any damage?

        • The hydraulic system is fully mechanical, with no electrical or cut out valves.
          If all hydraulic movement has stopped working you will need to check if the pump (mounted to the LH side of the engine timing cover) is still turning. There is an small shaft in the adaptor housing which maybe damaged.
          If you still have some movement in the hydraulics, but no real power, the main relief valve (fitted to the Dozer control valve – input section) maybe at fault. Pressures will need to be checked with a test gauge.
          Hope this helps,

    • Hi,
      No, the charge pump will not affect the drive as you describe.
      Check –
      1) brake neutralizing valve for stickiness.
      2) mechanical failure within the transmission – crownwheel & pinion.
      3) mechanical failure in the final drive.

      Drain the oils in transmission & left final drive & look for debris….

      My money is on mechanical failure, sorry.


      Andrew Frino

  • my 1150 case dozer torque converter stops ( output shaft to the trans stops or turns very slow) when the machine gets warm.
    Temp never goes past the edge of the yelow. If i pile snow on the trans and wait 10 mins, it goes again for 15-20 mins and than the same thing,
    Pressure drops and stays low for a while then comes back up, but the machine doesn’t always move even when the pressure comes back.
    any ideas?

    • Hi EJ,
      I’m assuming you have a straight 1150 (with no letter model)
      My first thoughts are is the transmission charge pump ok? This would need to be tested with a flow meter.
      If that is ok, you would consider the torque converter to be suspect.
      There are a few things that can cause pressure loss & they are all internal problems requiring converter removal.
      Andrew Frino

    • Hi John, to be honest I can’t recall if there are plugs behind the flywheel, it’s been too long since I have looked in that area on a 504 engine. The parts book only shows 1 plug & that could be for the camshaft.
      Sorry I’m not more help to you but I’m away atm & don’t have access to any service manuals.

  • I have a case 450B, trans charge pump is pushing fluid into my engine after running 30 minutes or so, i have changed the charge pump 3 times now,

    • Hi Chris,
      Are you sure the fluid entering the engine is transmission oil?
      Perhaps it is diesel fuel, due to leaking shaft seals at the injector pump.

  • it is probally very evident that computers are not my forte. however i will give it a try.
    I have a 1150b track loader that is used on farm. It has a401 case diesel which gave up.
    I have located a 401bd which is from a 970 agri-king farm tractor that a mechanic says will probally fit,
    but before purchase and labor I figure another opinion might be wise.(All the machinery and engines are case)
    I offer my thanks in advance for any advice.

    • Hello Perry,
      I have seen many agricultural engines fitted to construction machinery over the years. If they are both 401’s , I would also assume they are the same or similar block. The online part numbers available shows they have different part numbers for the engine block assy, but I would still think the ag engine will bolt into your 1150b.
      Interestingly, the parts listing shows a 451b to be the engine fitted to an 1150b…….

      I would go ahead with the change over, but look closely when the engines are side by side.



  • i just got a 1150d dozer. there is a steady drip coming out of the flywheel houseing. is it a torque seal or charge pump seal. how can a person tell. can to high of pressure cause this as well. and what is converter running temp

    • Hi Mark,
      If the leaking oil is clean, the leak is most likely the main seal on the torque converter. These machines have an external charge pump located on the rear of the converter. The transmission operating pressure should not affect the leak as the seal controls the lubricating oil inside the housing.
      Standard operating temp should be around 90- 95 degrees Celsius


    • There are two breathers on transmission. One on the filler pipe & one under the right armrest which uses a plastic recovery bottle. I have seen the recovery one overflow when the filler pipe one is blocked.
      If it is leaking out the filler pipe breather, there is excessive oil movement, perhaps caused from a leaking clutch pack.
      Does the transmission oil have air bubbles/foam in it if you check it shortly after running it?

  • ill check about the foamy oil but did not recall any bubbles. the oil is coming out the breather on the left hand side mounted on the side on the fuel tank not the filler pipe. i seen that recover bottle but there is no hose connected to it. what seal in the torque do you think is leaking. is there kits to buy or find a rebuilt one.

    • There is not normally a breather in the location you are describing. There should be a small rubber hose from the top of the transmission connected to the recovery bottle, perhaps someone has connected another breather to that hose? You need to check that out.
      You need to clean that breather at the transmission filler pipe.
      The seal is the main one in the centre of the housing, it’s about 8″ in diameter.
      Rebuild kits were available from CNH, however they were expensive due to a lot of unnecessary items being in them. I usually buy individual items. The seals are also available from bearing suppliers once you have it out for a sample.
      Here’s a link to CNH online parts search using your model.

      I strongly suggest you purchase a service manual if you already don’t have one. EBay is a good source. Also join an online forum like – this one is great for advice from machinery owners & repairers. I am a regular commenter there.


  • ok. ya i just got a service manual. some things are explained well and some stuff is not. not much trouble shooting for trans or converter.

  • hi. i just changed the trans and hyd oil and filters. let it ideal for for 5 to 10 mins and checked the trans oil. there was little bubbles on the dip stick. it may some air in the system cause i have the filter out and had suction pipes off. should i run it longer and drive it around. and check again. what do you think is causing the bubbles. as i said it was pushing oil out the breather befor.

    • Hi Mark,
      It is possible that the air could be from the short amount of time the machine was run. You should run it for longer & see what happens.
      Bubbles usually are caused by pump cavitation, that means the pump is sucking air somewhere. If the suction hoses are hard, this could be a cause, also if the charge pump is worn.
      It is also possible to create air bubbles If there is a large internal hemerage in the transmission, this can be isolated by conducting pressure test of the each individual gear range while the transmission is hot.
      The breather in the transmission oil filler pipe should be periodically removed & washed in some solvent or fuel & blown with compressed air.

  • hi. there is no breather in the filler pipe its a rubber type plug with a t handle on it and dipstick. the filler pipe goes into the lower part of the trans below the oil level at the back of the trans D E are like this. the C and older had the with the breather in filler pipe. do you think a breather or recover bottle is better.

    • Mark,
      I am very familiar with 1150D & E transmissions. There is a porous bronze breather inside a hex alloy retainer which is located at the rear of the filler pipe near the dipstick, look for it, it’s there for sure.

  • Hello, I have a Case 1150B dozer, serial #7306336 that has a transmission issue. The left side forward and reverse are strong. The right side forward and reverse do not work. When you move the right side lever forward or back wards you can hear a little pressure or something “hit” but the right side doesn’t move. I changed the two canister transmission filters which were dirty and it helped the left move even stronger but the right side still doesn’t move. I’m going to see today if the right side levers move the valve spool but beyond that do you have any ideas or suggestions? Thanks in advance!

    • Hi Mark,
      Did you drain the transmission oil when you cleaned the suction screen? Was any metal present in the screen or drain pan?
      Is the RHS free wheeling or does it lock up?
      Drain the final drive oil also & check for debris.


      • The transmission fluid did not hit the dip stick when I got the machine, I just added 5 gallons of HyTrax fluid to the transmission and I did not clean the suction screen.
        The RHS is free and rolls.
        I will check the final drive.
        Does this machine have 2 separate transmissions, one for each side, or just one transmission for both?
        Thank you for your reply and time.

        • The final drives are both separate from the main transmission, using hypoid gear oil. If the final drive drains clear, I would next drain the transmission oil & inspect the screen, maybe you will find a clue.
          Loss of drive in all ranges is not a good thing. It can mean a problem with crownwheel & pinion or final drive.
          If the oils are clear you need to inspect the RH brake spool at the transmission control valve. It is possible it may have broken a spring causing neutralizing of the track.
          Fingers crossed….

  • Looking at buying a 1970 case 450C. The left side drive works in high and low, the right side works in high and when put in low the track stops turning. Any ideas of what could be causing this?

    • Hi Jim,
      Likely it will have broken oil control rings on the RH hi/low shaft. Which means oil pressure has been supplied to the two ranges at the same time.
      If used like this for a long time the clutch packs are burnt out.
      Only a guess Jim, some pressure testing may help confirm the problem. Also inspecting the transmission suction screen may shed some light on it, by seeing what type of trash maybe present there.

  • hello. i have a case 1150d. was was running it for the day and noticed that when i put it into for or rev it makes a clunk noise that i have not notice befor. seems to operate as it should. any ideas. it has newer oil and filters in it.

    • Hi Nick, There could be any number of reasons for the new noise.
      Firstly, take a good look around the track frame to see if any thing has come loose or maybe a rock has jammed up in the sprocket area?
      Check also if the track idler bearings are still OK.
      Finally, drain your oils at the transmission & LH & RH final drives & look for any metal/teeth etc.

      Hope this is of some help to you.

  • I’m looking at buying a 850h the seller said that the right side has engagement disengagement issues and sometimes does not want to drive on that side any ideas

    • Hi Jesse,
      There could be problems with oil pressure control rings fitted on the end of the high low direction shafts. These act as seals to stop oil pressure going from High range & Low range. If they become worn or damaged when you select, say, high range left – the worn seal rings allow pressure to be sent to low range left – at the same time. This causes both ranges to be engaging at the same time – acting as a brake & usually causes clutch pack friction discs to get hot & wear out prematurely.
      You would need to test the transmission pressure & compare the difference between engaging LHS & RHS – there should be a noticeable difference in pressure due to the internal leakage.

      If this is the problem – the entire transmission would need to be removed from the machine to enable repair to the seal rings – as the hi/low range shafts need to be removed from the front housing to service them.
      BIG job – lots of $$$$ required.

      Regards Andrew (aka alrman)

  • I have a large ih track loader its old I don’t no how old it has a671 motor its at least a 250 the tracks r waste hi and the seat is 6 ft up it will pull at hi rpm’s but will not dig it has a dr shaft out of the tarkconverter and it stops turning win u dig

    • Hi Mac,
      Unfortunately, I don’t have alot of work experience on old IH construction equipment.
      Typically, you will need to check some pressures to see what is going on.
      You may have a problem with the torque converter or the transmission pump or individual clutch packs inside the transmission.

      Sorry I can’t be more specific


  • Have a Case 850 D dozer was pushing a load and all of a sudden it acted like it just went into neutral and won’t move now but the blade still works fine ?? Any idea of the problem ??

    • Hi Larry,
      Is it possible the mechanical hi/low range lever – located near your left ankle has been bumped into neutral?
      Is the driveshaft still connected to the transmission?
      Is the driveshaft spinning while attempting to drive?

      Hope this helps


  • Hi Alrman. I have a case 1150E, just hit 8000 hrs owner driven. Converter temp has started rising towards the high end of the green, is worse in 2nd gear and not necessarily doing hard work but its slowly getting worse. I blow the coolers regularly but dosen’t make much difference. The oil cooler was new about 1000 hrs ago, I’ve changed trans oil and checked suction screen it was clean. I just had the trans filter off beside batteries and the oil does have a bit of a burnt smell. Do you have any ideas where I should start to try and fix this. Thanks

    • Hi Campbell, my first thoughts are that there could be problems with oil control rings inside the shaft endcaps.
      At operating temp, at engine idle click through each gear & check transmission pressure. It needs to be the same on each gear selection & take the same amount of time for each gear selection.
      Lower pressure, slower selection indicates you have a problem.
      If the seal rings are damaged, two different clutch packs will be engaged & that is like driving with the brakes on & superheats the oil. If the machine has been operated for a long period of time like this clutch packs will be burnt out.



      • Thanks so much for the advice. I will check that out. If that is the cause I guess I’m up for a major cost. Can you help with parts/kits? How long does it take to get the trans out?

        • It depends where the problem is with regards if you you need to pull the transmission.
          FWD & REV are accessible through the rear cover.
          I don’t really deal in parts, many parts have to be genuine.
          You may find some used ones for major components.

          • Hi Alrman, following up on this my converter temp is getting near the end of the green, I have reconnected the trans pressure gauge, its running like nearly full pressure while working, all changes at idle are identical and I would not say delayed. Where should I turn to next? Thanks

  • Hello Airman, I have a Case 450b. Runs fine, but after 30 minutes it starts overflowing tranny fluid over the fill receptacle under the seat. It was not overfilled prior to starting. Any thoughts would be much appreciated .


    • Hello Tim,
      There are clutch packs that are turning very near the filler pipe.
      My thoughts are that at least one of the packs is haemorrhaging more than it should & is flicking the oil towards the opening.
      At operating temperature, click through the gear ranges – at engine idle speed – the transmission pressure should read the same for each selection & also take the same amount of time to engage the gear.
      Lower pressure & delayed gear selection indicates where your problem is.


      Andrew (aka alrman)

  • Hi again, our 1150e has a breake shudder. When turning downhill slightly and try to gradually brake it starts shuddering, was only doing it on one side but now both do it, bloody annoying. Any ideas please?

    • Hi,
      Usually shudder noises are related to oil problems. Have you recently changed the oil? Different brand or Viscosity?
      Maybe the oil in the transmission is well overdue for a change?


      • Thank you for your response. Those are my symptoms but I took my charge pump apart and it looks fine. The gears seemed good. No leaks. I’m curious what a worn out pump looks like inside. What should I be looking for?

        Best Regards

      • Think I found the problem on my transmission on the Case 450b. Checked my engine oil dipstick and it was at least a gallon overfilled. The charge pump was leaking thru the shaft seal. Even though upon visual inspection it looked OK. I wish you guys were in San Antonio, Texas. Can’t find good heavy equipment service here.

        Best Regards

        • Hi Tim,
          sometimes the pump leak is due to wear at the bearing blocks closest to the input shaft seal. They turn in towards each other, due to the rotational forces of the gears.
          Then they can either draw air into the system, taking a long time to build pressure at start up OR they can leak transmission oil into the engine – as has yours.
          A new charge pump is the best repair option – I don’t think CNH has too many parts to rebuild those old pumps.

          • Hello Alrman. I have an 1150B loader. I do not have low range on right side track. I have changed the steel rings in the cover. I have also swapped high and low hoses to verify the valve body is functioning. My pressure gauge drops real low and fluctuates when put in track low. I’m pretty sure the seals are blown on the clutch pack.

            Have you ever changed the seals with the transmission in the machine? I know there is not much room. Thank you.

          • Hello John,
            No, I’ve never pulled the front cover from an 1150 while the transmission was still fitted to the machine – and I wouldn’t recommend that type of repair to anyone either.
            Less than a days work & the transmission would be out of the machine – clean – ready to work on in comfort.
            Hope this helps you make up your mind

  • I have an 850G Dozer, r/s high (Forward and reverse) has never operated so always run in low, decided to try to tackle problem, swapped r/s and l/s- hi Lo shift spools and lo and behold rs high came to life, left side high forward inoperable But has ls high reverse..figured bad spool, ordered new spool put in left side hi lo, still no Ls high forward…what the??!! Did I accidentally swap brake spools left and right while I was rebuilding control valve and that is what is affecting left high now?? Book shows check ball in brake spool, hmmm. Finally found diagnostic manual with pressure and flowmeter specs, suction screen clean, fluids all clean as can told me needs new trans 15 years ago, not thinking so.

    • Hi,
      Those spools can be very finicky…. so many springs & valves.
      I would swap the spools again – the Right spool back to the left & new spool to the right see what happens?

      It’s possible that the new spool has been sitting in stock for a long time & one of the valves or balls maybe sticking?
      You would have to let the CNH dealer know about your situation & see what they suggest. Whether they supply another spool or their service department take a look at it.


  • Yup, I requested a “quality control check” on the spool they sent me. They verified that it was an updated version as the end was hollow versus solid like the old, 60 degrees out tomorrow, 8 inches of snow coming Sunday so we’ll see how motivated I get..
    Think your right about swapping, they are finicky. I will do that inspect, and post results.

    Having similar issue on a Komatsu D-65 r/s steer lost clutching, brake is good its an older -6 so probably control valve/ pressure to rs clutch I am guessing…Think I found an old manual..

    Thank you!

  • I have a 1971 Case D350, NOT a B model. I had a bad leak on the front of the shuttle shift and after a short while of pushing the dozer would stoop pushing as if the clutches were slipping. I decided to just rebuild it while I had it out so I have all new clutches and seals and now when I crank the engine the driveshaft turns quite fast and it has no power to push anything. it will move in first gear but no power to even fill the blade. wondering how to test the charge pump or the torque converter or if I didn’t get something correct on the inside when I put it back together?

    • Hello Kevin,
      There are many things that can wrong during assembly.
      It’s easy to damage piston seals while installing them into their carriers.
      The two small teflon rings on the end of the shaft are also easy to damage.
      If any of these seals are damaged – oil pressure is lost.
      The forward clutch pack clearance needs to be adjusted correctly.
      The forward clutch hub/drum needs to be assembled correctly – belville washer installed correct way & .093 snap ring used as a spacer between plates & piston.
      A worn pump can also affect drive – pressure test required.
      Any of the above + more can affect drive upon completion.

      You would check the converter by means of a stall test – Placing the transmission in high range & by pushing against a large pile of dirt or tree – seeing the difference in engine rpm with no load & full load (the tracks must not turn) – stall specs are 2100rpm no load – 1800rpm full load.
      During the test If the tracks aren’t turning – the driveshaft mustn’t turn.
      Too many rpm at full stall indicates slippage in shuttle/converter
      Too few rpm – indicates either poor engine power – fuel restrictions (if engine power is OK) a bad Converter (sprag is damaged) = new or repaired converter required.

      I hope you have a service manual? To guide you through the rebuild?


      • Thanks for the reply, I have the shuttle without a removable base pan so I don’t have some of the seals you referred to. Also I do not have a manual of any kind for this machine, I bought it for next to nothing, not running, and leaking from the front seal of the shuttle shift. I simply replaced clutches like for like and seems like the problem have been exaggerated, except for the leaks. I did use the thickest clip ring that would fit when installing the clutch pack. I’ll try and see what the test you mentioned will reveille. Thanks

        • Ok, I verified a few things inside the shuttle and re-installed the shuttle with new fluid and as soon as I cranked the machine it would drive in third gear but would not push under load the engine rpm would not drop but it would spin the tracks in second gear with no hesitation. after about 10 mins of pushing a light load the machine would not even move in 3rd gear and would not push any load at all in 2nd gear and engine rpm did not drop. if it was something i did inside i would think it not push anything right out of the gate, am I thinking correctly?

          • Hi Kevin,
            If all is good with the forward clutch pack, & you have reasonable drive when oil is cold. It does point towards a worn charge pump – I would however pull the converter & get it overhauled.
            You would need to take it a specialised repair shop, as they need to be cut open on a lathe & welded back together after new items are installed & then pressure tested.


  • Greetings, I have a 1150b with a bad radiator and trying to remove transmission cooling so I can remove the radiator. Is there a special tool or trick in getting those lines disconnected ? Thanks Rick Houston

    • Hello Rick,
      If I recall correctly, the oil cooler hoses are UNO fittings at the oil cooler fittings – meaning they don’t swivel – That is unless someone has not modified the hose configuration over the years…..
      You would need to first loosen the other end of the hose (about 12-14″long) where they connect to the steel lines which run along the chassis. Then remove the hoses at the oil cooler fittings. OR then pull the radiator with the hoses attached.
      Sounds easy I know, but the restricted work space makes it difficult.

      Google “crows foot socket” these tools can help in this situation.


  • Hi, I have a 1981 case 850B I bought several months ago. Has ran good for the couple hours that I ran it. Out of the blue I was running it and as soon as it got up to temp the right track did not operate normal and then it just quit. Left track had no issues. When temp cools back down it will work again until it warms back up. Any info would be great thanks.

    • Hi Ryan,
      Could the brakes be dragging? How do the pedals feel?
      Is the transmission pressure gauge working? Does the pressure drop more when you engage RH forward the reverse?
      Does the pressure drop more in RH low or high?

      Look for more symptoms to help in diagnosis.


  • Hello, I have a 1983 Case 1150D dozer. I noticed that the transmssion oil pressure gauge needle was starting to fall in the yellow/gold section of the gauge and would slightly be in the green area at times when operating. I connected a digital gauge to the gauge line so I could get psi readings.
    When starting out at cooler operating temp the gauge read 269 to 270 psi, then at normal operating temp at 2,000 rpm under medium loads read 246 to 251 psi. It is my understanding that the normal psi should be 250 to 310 psi or damage to the clutches may occur.
    The converter temp is running cool. Dozer seems to still be operating correctly.
    Do you think my transmission charging pump is starting to fail or is there anything else that I need to troubleshoot?
    Thanks Rob.

    • Hello Rob,
      While your pressure is low, it is still within spec. If the pressure has dropped within a few days or even more quickly, it’s possible you have an internal haemorrhage occurring somewhere.
      It’s unlikely that a pump will suddenly lose pressure, but not impossible.
      If the transmission pressure has dropped in a short amount of time, take note of the pressure with individual ranges – at an idle & at operating temperature.
      If the pressure is low in all ranges, it is possible that the pressure loss is occurring in the transmission control valve – blown gasket or broken spring somewhere.
      If the pressure loss is more noticeable in a certain gear range – then you need to look at oil control rings under the shaft end caps to begin with – if they are OK, then you need to look at clutch packs……

      Hope this helps


      • I’m having low pressure as well. Blew gasket on control spool. Changed it out Ran about 30 mins and lost pressure. Pressure is about 120. Changed charge pump. Didn’t fix it. Looked at pick up tube, and it was clean. As well as all the filters. Actually put new ones. I’m stumped now. Any ideas as to what to do now?

        • Hello Shawn,
          I would think there is still a problem in the control valve, perhaps the other main gasket? or even the new one you fitted?
          May also be worth checking the variable orifice spring located behind the rear triangular plate of the regulator spring.


      • I hve 1150 D with low transmission pressure 130 psi. Changed charge pump. Checked filters. Checked suction tube. Checked pressure relief valve. What am I missing? Started out it blew control spool gasket. Changed it. Ran for about 30 minutes and lost pressure. Any ideas as to what to look for now?

  • Alrman – Stumped on an issue with a ’72 Straight 1150 Loader miltary model with detroit 453. Bought the machine with a siezed motor. Did an inframe rebuild and it starts/runs great, plenty of power. The machine is very sluggish and hardly moves. Suction filter was clean but had been replaced fairly recently i would guess. Replaced charge pump, machine moved better, it could turn with one forward/one reverse track. It ran for about a day then got rapidly worse. Internet searching lead me to suspect converter. Dropped converter and did complete rebuild of tubine assembly with all new parts, bearings, seals, including hub and gear that were badly worn. Flexplates were destroyed. Figured, I’d get her back together and be doing track stands! Once back running I still have no power, I’m stumped and very puzzled/frustrated. Please HELP 🙂

    • Hello Chris,
      I’ve never actually seen one of these military 1150’s – I can only assume that the converter & transmission are factory standard.
      You need to take notice of the transmission pressure gauge during operation – at an idle click through all the gear ranges.
      If the pressure is low in all ranges but the similar, there could be a problem in the control valve, gasket, broken spring etc
      If the pressure is low in one particular range, then you need to check oil control rings in the end caps….. to start with….

      Hope this helps


  • Hello i have a case 1150b that suddenly lost trans presure i have around 230 charge presure and my drive shaft is spinning free when i start machine, ive cleaned and replaced gaskets on control valve under seat, i can feel it go into gear and it trys to move, is there anyway to know if its my tourqe converter thanks

    • Hi Cody
      Torque Converters are difficult to pin point as a problem.
      Usually they don’t fail – all of a sudden – Often the aluminium turbines touch & put a fine metallic fleck in the transmission oil.

      230PSI is a little low in pressure – it is tested at 2000rpm.
      Could be charge pump, could be leaking internally in the converter, could still be something in the control valve that you missed??

      The transmission modulator on the B series I recall was connected to the brake pedals? Anything binding up & causing the modulator to be activated?
      Try disconnecting the linkage to see if it makes any difference.



  • Have 1150B after I fun it 30 to 40 mins starts taking fees second to move when in forward, then after few more gets worse, reverse still moves fine. Then totally loose both. Can you help me in right direction.

    • Hello Ray,
      It’s very difficult to be precise.
      Transmission charge pump could be suspect.
      Torque converter could also be suspect.
      There could also be clutch pack issues – with forward losing drive before reverse.
      Could be any one of these issues or a combination of two or more….

      You will need to avail yourself of workshop service manual & carry out some pressure tests, hopefully to narrow the problem down a little.



      • Thanks. Had torque converter rebuilt (needed it anyway) but still doing it. I’ll check on other two possibilities. Thanks again.

  • I recently purchased a 80’s Case 450B dozer.
    Having an issue with the right track. When it’s cold it starts up and works great. When I step on the right turning break, I lose the right track. I pull halfway up on the emergency break and it comes back. The breaks aren’t sticking cause it still rolls. I can do this about 5 times before it won’t come back at all. After the about 5th time I lose the track, it first feels like it’s slipping, before it completely stops.

    • Hi Tim,
      Firstly, you should avoid using the brakes to steer the machine. They were designed to be steered using the hi/low range shift levers. Use the brakes sparingly in tight manoeuvring & on steep terrain.
      The previous owner may not have used the brakes & now their operation could be affected.
      There is a neutralising valve for each track attached to the transmission control valve – just trace the brake lines & you’ll find them.
      These could be sticking & causing your problem OR the brake slave cylinders may not be returning properly.

      Does the transmission pressure gauge still work? It should between 250 – 300 psi @ 2000 rpm.

      Hope this helps



  • Hello alrman.

    I have an 1150b track loader. The loader lift arms drift down quickly about 2-3 inches when the control lever is released. After the initial quick 2-3′ drop the cylinders continue to slowly leak down. I repacked the cylinders about 4 years ago (100 hours) using genuine Case kits. The loader has always drifted down slowly I just assumed it was a leaky hose. I have now changed all the hoses and o-rings on the fittings. I see no visible leaks anywhere in the loader lift system. I don’t think the pump is sucking air either, all return hoses and filter screen have been changed.

    Before I open the cylinders back up to check the packing is there something else i can check?

    Thank you

    • Hello John,
      It is possible the load check valves or their springs are at fault. However, the problem usually lies with the cylinder piston packings. I would still visually check them first before looking for anything else.



      • Mr. alrman you were correct the packing is toast.
        The bolt backed out of the rod about an inch. Thankfully I decided to pull it out. Cylinder bore looks good no scars or scratches. The steel piece (bearing?) between the packing actually looks better than the other side.

        Hopefully Miller Brewing does not cause this problem again.

        Thanks for having this site and answering questions.

  • Need of some dozer wisdom. Checking for neighbor who has a Case 550e that is losing transmission fluid very quickly, yet and very bewildering no leaks are found anywhere. A few of us have searched the darn thing and just can’t come up with clue. Again lose is about two quarts in two minutes and no signs of leaks.

    • Hi Heidi,
      Hope you have this fixed by now…..
      If you can’t see any oil leaking out of the machine, there is a difference in oil level on the dipstick before you start & if you check it shortly after the machine has been running….. could this be your issue?
      If the level is falling due to leakage & you can’t see anything externally – it could be leaking into other compartments – could the engine bell housing be filling up? OR the final drives?


    • Hi John,
      There are many things that can cause your oil leak. Pressure & suction hoses & also steel lines that can rust or wear through………
      You will need to remove engine covers/floor plates & try to locate which part of the machine is the wettest with oil.
      That may also involve removing the belly guards to locate the source of the leak.

      Have fun!

  • 1150c career tractor no reverse forward works fine original issue was no low but the tractor went forwards and backwards, rebuild clutch and install now won’t go backwards any ideas? Pressure for the hoses with an in-line gauge 276psi

    • Hello Frank,
      When you say you rebuilt the clutch – I am assuming you removed the rear cover of the transmission?
      Could the top shafts have moved out a little when you pulled the cover?
      Are you 100% sure the range hoses have been refitted in their correct locations?
      Do any of the tracks attempt to move with the engine running, machine raised off the ground & in neutral?

      I need a little more info to give more specific advice


  • I have a 1970 450 case dozer and im loosing transmission fluid and today i found it . It is going into the final drives . Can u help me .

    • Hello Leo,
      There is a seal located on the final drive crownwheel shaft to stop the oil transferring from the main transmission housing to the final drives.
      The early 450’s have a slotted nut that tensions the bearing preload for the crownwheel shaft. It’s possible that this may have loosened – but unlikely it can happen at the same time for both sides….
      If it has loosened, it’s possible that there is a problem with the actual bearings on the shaft failing.
      If so, there will be metal flakes present in the final drive oil.
      To gain access you need to split the tracks & remove the drive sprocket to remove the upper inspection cover.

      It could be that the seals on both sides are just too old & have failed. To replace the seals – the final drives need to be removed from the transmission & dismantled – not an easy fix – sorry….



    • Hello Milus,

      Generally what you are describing is a lack of drive in high or low range on one side of the machine.
      I’m not sure exactly which side with your description.
      Do any of the transmission pressure gauges still work on the machine?
      If so, can you tell me what happens to the pressure when you engage high & low range on the faulty side?
      A little more information is required to be able to help you.



  • I just purchased a 1150E, hyd lines were so bad I could not “test” drive. Got all them fixed and the LH reverse does not work and the trans gauge drops to nothing, other than that it seems to operate fine. It has 6k plus hours on a broken hour gauge but the machine does not appear to be abused. Fluids look clean and full, no noises, when shifting from low to high it feels like it gets a little but the trans gauge does not move.

    • G’Day Brad,
      First thing I would do is to be certain the new hoses are connected correctly.
      LH Rev shaft end cap is located at the rear of the transmission on the upper LHS (standing at the rear of machine facing forward)
      2 x hoses are connected to the end cap, the hose on the outer fitting is LH FWD – the hose closest the main housing is LH REV.
      First, loosen LH REV, start the machine & engage both HI/LOW levers & LH REV – see if you have pressure there.
      IF no pressure, double check all the new hoses, then triple check.
      IF you have pressure, swap the FWD & REV hoses & see if the loss of drive then goes to FWD or stays at REV.
      If it FWD loses drive there is a valve problem – if the problem remains in REV – you have a transmission problem – likely a damaged clutch pack……

      Be sure the brake pedals are not “hanging” & the brake spools are moving freely.

      If you don’t have one yet, I strongly suggest you get hold of a service repair manual

      Cheers from DownUnder


      • I only changed the blade hoses. Switched the LHR & LHF and still have the same result, LHR does not want to engage it pulsates the track slightly. Can you change out clutch pacs without pulling the trans? I got factory manuals but they only go thru the whole trans rebuild. The trans filter looks pretty old, I did pull the small inline filter screen on top of the control valve and it was very clean, any other suggestions? Thanks.

  • Have a 850d long track case bulldozer working fine then no drive forward, reverse is fine, still strong came up out of gully pressure gauge still in green in forward and reverse all oil levels good, have had machine for 10 years maintained well complete new under carriage 2 years ago, all filters & oil regularly, reverse working in low or high good, no noises, any ideas thanks Andrew.

    • G’Day Andrew,
      If the transmission gauge is showing pressure when forward is engaged & there is no drive happening, it would indicate that there maybe a problem with the forward clutch pack.
      Swap the FWD & REV hoses at the rear of the transmission (the PTO housing) & see what happens when you put the machine into FWD – it should drive in REV – indicating that the pressure supply to the clutch pack is OK.
      If when you put it in REV, it should drive FWD – if no drive occurs – it would indicate that the problem is in the FWD clutch pack – likely all the teeth on the clutch plates are gone.

      When you did the transmission servicing – was the transmission suction screen inspected?
      I would suggest to drain the oil into a clean container & check for debris & certainly take a look at the suction screen as it will catch any material caused by worn clutch plates.



  • I have a 1974 case 450 crawler the right track is locking up like the brake is being applied and i have to put it in to reverse to to move it what do you think could be wroung?

    • Hi Russell,
      Firstly, I would be sure nothing is getting jammed in the track or sprocket – like a rock.
      Next, using a long crow bar, see if there is any excessive movement in the sprocket/axle area – use the bar to also check the front idler bearing.
      If they are OK – drain the final drive oil & see if there is any broken teeth in there.
      If that is clear – drain the transmission oil & look there.
      If you find metal pieces in the oil …… well it’s time to loosen the purse strings……


  • Hello Sir,
    I’ve been following you and your responses across many blog sites, you’re very helpful. I just recently purchased a Case850D, 4600hrs, runs great. When cold, the forward/reverse & high/low levers shift correctly, the pressures act the same when flipping levers. When the machine has worked a bit and is hot, the right track doesn’t respond quickly getting into gear, sometimes not responding at all. However, if you wait for it to engage that right track, the track seems to move strong. Also, that right hi/low lever seems incredibly loose has little to no resistance (compared to the good left track) which was making me think there’s some issues with the valve, maybe a bypassing spool valve? I would love your input. Kind thanks, Brian

    • hello Brian,
      Thanks for the compliment.
      There is an adjustment for the detent on each direction spool at the transmission control valve – similar to an engine tappet.
      The right control spool will need a little tweek to tighten up up spring tension to make the control selection feel firmer.
      I wish the drive issue was as easy to fix.
      Need to see if the system pressure is low or just individual circuits are low, due to internal haemorrhaging.

      There could be issues with the oil control rings on the RH transmission shaft. If worn or broken, causing loss of pressure & maybe sending pressure to both Hi & Low at the same time.
      Unfortunately, you need to remove the Brake housing to remove the RH shaft end cap – to carry out the inspection.
      If the transmission has been operated like that for any long period of time, the clutch plates get worn as they drag/fight against the other mating clutch pack.
      What this means is the transmission needs to be opened up to check for damage.
      Just a hunch, But you will need to check pressure on supply to the Hi & Low packs & then T into the circuit to see how much pressure difference there is.

      Draining the oil & checking the suction screen for any debris is always good to do as well.


      • Hello Alrman,
        Thanks very much for the response! To date, i’ve taken the control valve off and inspected teh 3 spool valves, nothing seems out of place there. (i think you’re probably about right about the detent, but that’s not a huge issue)

        My question now is in regards to Number #6 in the diagram:

        This is what i believe is a clutch cutout piston, and the one side seems much stickier than the other side. I also noticed that there was nearly no fluid in the bad side. I see that there are brake lines that connect to this spool and i’m wondering now about how the the brakes could be causing issues here. More to come, thanks!

        PS- Is it worth takign apart the TRANSMISSION MODULATOR VALVE ASSEMBLY to inspect it for anything odd?

      • Alrman,
        I thought I’d share with you news about the right track not working. So it turns out that the master cylinder had a clogged ‘return’ hole which would not allow fluid to come back into the master cylinder, and would then de-clutch the machine. In other words, you step on the brakes, and the machine would de-clutch and not re-engage for a while.. crisis averted!

        Unfortunately now, I’m having issues with the blade hydraulics losing power and speed when the machine heats up. I suspect a pump but will check filters and screen first.

        thanks again for all your help.

    • Hi Brian,
      They are item #13
      To inspect them, you must remove the RH brake housing & remove the end cap with the two hoses going to it.



  • Hello Alrman,

    How difficult is it to rebuild the transmission with new clutches? Are forward/reverse, high/low clutches all typically last the same amount amount of time? Is this considered one of the more difficult undertakings?

    Also, I have the factory service manual, but I feel like it often lacks detail. For example, that manual doesn’t even give you a hydraulic schematic overview of the entire machine. is there a more detailed manual you’re aware of perhaps?

    Thanks again,

    • Hello Brian,
      The amount of labour involved is around 100hrs with someone who is familiar with doing the job.
      Depending on one’s level of mechanical repair capabilities, the average person will not be able to perform the task, as there is also a bit of tooling that will need to be fabricated.
      The entire transmission needs to be removed from the dozer & it needs to be laid on it’s back to do the repair, so serious lifting equipment is also required.

      Hence you really need to be certain of where the problem exists to warrant going inside the transmission.

      The service manual is what it is for machinery of that era.

      It may pay to have a diagnosis made by someone with some transmission repair experience.

      Hope this helps


      • Alrman,

        100 hours??! Wow!

        How often have you seen such clutch failure to warrant that type of work? Would you be surprised to see this at 4700 hours?

        I will remove the brake housing as you mentioned and inspect those seals as you suggest.

        Thanks for your knowledge!

        • It would be surprising to see clutch failure at 4700hrs.
          But more surprising to see a 1970’s era d850 with that number of hours under it’s belt.
          Sure it isn’t 14700 hrs?

          • This is an 850D, later model. it’s probably early to mid 90s i believe. It’s been sitting for probably the last 15 years doing nothing. I can send you some photos via email if you like!

  • Hello Alrman,

    Have you ever seen the dozer lift circuit exactly half the pressure of the tilt and angle circuits? In my case, i can’t get the loader lift to go to full 2000psi UNLESS i also engage the tilt/angle at the same time. I’ve elimiated the lift cylinders by capping/plugging the lines so i know it’s not the cylinders. Thanks,

    • G’day Brian,
      You will need to reseal small shuttle valve located in the rear of the lift section.
      Gain access from under the operators seat.
      There is a small ball bearing in there – so lay cloth across the entire area in case it falls out during removal process.
      You will need to buy genuine seal kits as the orings are a hard white material.
      A specialised hydraulic seal supply store may have the correct orings.
      I would reseal each section as they may all be in similar condition.


  • Hello Arlman,
    We have I believe a 1978 1150B track loader. Everything really works well except the left track has no power in reverse (it will coast). The hydraulic pressure gage is a bit low, just into the green with both tracks in forward or with the left track in forward and the right in reverse, but anytime the left is in reverse it cuts the amount of pressure about in half. High or low doesn’t seem to change much. We are wondering if we should look at the control valves under the seat or should we be focused on the oil control rings at the rear of the left clutch pack?
    Or is the problem something different?

    • Hi Alan,
      I would undo the LH REV & FWD feed hoses & check the pressure directly at the LH REV hose & compare it to FWD – confirming the supply pressure is the same or not.
      If the supply pressure is the same – then check the end cap seal rings for damage.
      If you don’t have testing equipment, you could swap the two hoses & see if the problem switches to FWD (supply problem) or remains in REV (Clutch pack issues).
      If the machine has been run with broken shaft seal rings for a long time, chances are that the REV clutch pack is damaged too.
      Checking the transmission suction screen may confirm if there are internal issues as well.

      Good Luck!

      • Alrman,
        My boy switched the lines as suggested and the problem stayed the same below but of course switched how it reacted with the levers.(left stick back track pulled forward, left stick forward little to no power in reverse) Sounds like the next step is to pull the end cap on the left side. It looks to us like we need to pull the counter weight to do this. Does that sound correct?

        • Hi Alan,
          By the sounds of it, yes you may need to remove the counterweight.
          I’m not 100% sure though, as 99.9% of crawler dozer/loaders here are fitted with rippers & you have easy access.

          I would check that suction screen asap – as it may confirm more diabolical problems whether clutch plate material will be present or not.
          Of course, you will need to drain the transmission oil to check the screen.
          If you drain the oil carefully into clean containers, & if the oil is not too contaminated with metal particles, you can put it back into the transmission.

          Fingers crossed!

  • I have a question regarding an 1150 E case dozer. When the engine starts up and runs should the driveshaft always be turning? The driveshaft does not turn when the engine is running and when shut off I can turn the driveshaft freely. I have no forward or reverse and no hydraulics.

    • G’day Kenny,
      Yes, the driveshaft should spin, while the machine has engine running & the transmission is in neutral.
      If you also have no hydraulic function, I would think that the torque convertor is not turning with the engine, due to a broken flexplate.
      If this is so, you will need to inspect where the flywheel & torque convertor spigot make contact, for any wear that has occurred because of this failure & also repair as necessary.

      Sorry for being the bearer of bad news,


      • Thank you for the information. Is there anyway for me to know if the torque converter is good after I put a new flex plate in? Without putting everything back together.

        • You’re welcome.
          Short of dismantling the torque convertor……. & you need a trained eye to know what you are looking for.

          Hope it all works out for you

          Cheers! 🍻


  • good sir. i am not sure if his thread is geared only toward Case equipment. Do you have a familiarity with old John Deere dozers? 1976 550. If not, could you point me in the right direction?

  • Hello Alrman,
    I have a case 1155d loader I bought several years back. It had suppose to have been motor and trans overhauled at same time 750 hrs ago. it runs great, pulls strong but after it starts heating up trans oil starts leaking from torque converter housing. I have removed belly pans hoping i had a loose line or filter leaking, but both are good. I removed 4 bolts on inspection cover and it is definitely coming from tourque area. The more you run the worse it gets. so i haven’t used much. The trans pressure gauge broken, I have done no pressure test of any kind. Any advice would be greatly appreciated.

    • G’day Tony,
      Unfortunately you need to remove the torque convertor to see what is the cause.
      There is a large seal that may have been damaged during installation – if the convertor was actually resealed during the overhaul.
      Worse scenario is that there is a number of 5/16″ bolts that bolt the convertor together. Sometimes the threaded holes crack & cause a leak to occur – usually caused by careless assembly, not clearing oil from the blind hole first…..
      Hope it’s an easy fix for you!



  • I have a problem with my 1155E every thing seems to work fine BUT after I replace a broken trans pressure gauge it tested at 280 psi but when I applied the brakes it dropped to 30 psi no matter if I revved the motor. When I put in drive, pressure came back up, but dropped when I took it out of drive!!!?? Baffled can you help?

  • Gday Alrman

    I have a case 2000 model 850H
    The coolant temp sensor is not giving a reading,
    I have tried fitting two brand new sensors neither of which changed it.
    When shorting out the single wire going to the sensor, the gauge spikes to full, which I’m thinking is telling me the gauge and wiring is sound.
    Could there still be a wiring fault or dicky gauge as the two brand new sensor did not fix it?
    Got me beat so was wondering if you’ve come across something of the like

    Cheers and thanks for any help

    True blue

    • Hi Callum,
      I can’t say I’ve had that sought of trouble with 2 new parts before. But if the gauge is moving when you ground the wiring terminal, it does usually indicate the gauge is good.
      Was the gauge ever working?
      Is there a thermostat fitted to the engine?
      Fit an aftermarket gauge?



      • The temp gauge has previously worked yes but can’t say for the thermostat, will have to have a look at that, I would have thought with out one it still would be registering some sort of heat,
        If we do no good an aftermarket gauge will be the next thing to try out.

        Thanks Alrman will let you know how it goes

  • Tony, I have a case 1155D loader. The transmission gage pressure will be in the green and then will stop working. The loader will move forward and reverse but real slow. What could be the problem?

    • G’day Tony,
      Problem could very well be any number of problems.
      Most likely the problem is in the transmission control valve, which could have more than one thing wrong with it – blown gasket / broken springs.
      Charge pump could also be at fault – flow testing is required to check it’s condition.
      Torque convertor could also be at fault with worn components.

      Keep Smiling

  • I have a case 850D was sitting about 5 years Motor runs Good Cummins Motor my Problem . when put it in gear no pushing power it will walk its self but is weak it has no pushing power PLEASE HELP

    • G’day Ricky,
      Unfortunately, Case transmissions can have a number of things that can cause low pushing power.
      Start with simple things by being certain oil is clean & at correct level, filters/screens checked & cleaned/replaced.
      Then pressure testing is required as without the proper pressure the system will not operate.
      There are good tips in my article above that will help diagnose the problem.
      If all else fails – you will need professional help.


  • Good day Alrman,
    I have read through most of the archived posts and responses here and am sure there is some great guidance for my issue but I am new to this troubleshooting thing and will as anyways.
    I have an older CASE (70s?) 1450 (not B) crawler/dozer. It had been sitting for two years. I had the rams repacked recently and attempted to use it after the rams had been repacked. It did not want to move in any direction in any gear. In discussions with the prior owner he stated he would have to let it run for 20min or so before it would move. Attempted that nothing. Then I decided to looke into the fluid levels. I discovered the transmission lever low/empty. I added 10 gallons of TCH fluid. Prior owner was not aware there was transmission fluid separation from the hydraulics. So I take it that he may have ran it low or heven forbid dry. Now full, it still does not move in any direction in any gear. It does however show signs of engagement in all direction and gears but no actual movement. I have not removed and cleaned the pressure or suction filters that was going to be my next steps.
    I have a full manual and parts book but am not the most mechanical inclined.
    Any assistance is appreciated.

    • Hi Jeremy,
      So many questions require answering here….
      10 Gallons of oil is almost a full refill – is that amount correct?
      How long have you owned the machine, & used it with low oil?
      How long have you now try to run the machine without movement? – the transmission pump could be toast….
      Do any of the pressure gauges work? What pressure does the transmission have at full rpm?
      Does the oil level in the transmission, go down once the engine is started?
      Did the brakes work on this machine?
      Are the brake pedals operating freely?
      If the oil transmission oil level is that low – where has the oil leaked out?
      Is the driveshaft spinning as a blur in neutral? Or just lazily? Does it stop spinning once a gear is engaged?

      There are alot of things to stop these things from operating.
      I really need more info to be able to help.


      • Alrmam,
        I am in the process of purchasing the dozer from my uncle. I have yet to use it. He has had it quite some time 20years. He was not aware that there was a separate fluid reservoir for the transmission, and thought it was shared between the hydraulics. So, he had run it with low oil fluid for a while. It last ran two years ago when a seal busted on a lift ram draining the hydraulics. It has sat ever sense. He did state that previously he had to let it warm up for 20 minutes or so before it would drive. I have not driven it yet. Only been able to repair the ram and replace fluids. Only attempted to drive the unit once before replacing TCH fluid and once after. The results after where better than before but still nothing more than the tracks tensioning the slack.
        Yes it was a full 10 gallons. Yes the level drops when the unit is running. Both attempts at running the unit the transmission pressure gage never moved. It is the only gage that did not respond. I am not sure if it was working prior or not.
        Breaks worked and operate freely.
        No signs of any oil leaks, just minor accumulation on the pan. I am not sure where the fluid had gone but it sounds like it had years to do it.

        I will inspect the drive shaft at the next opertunity (hopefully tomorrow). Will also attempt to pull and review the filters. It sounds like the unit operated reliably before it sat for 2 years without hydraulics. But it also had no transmission fluid during that time.

        Will report back with more information. Any thoughts on how to test the transmission pump?

        • Hi Jeremy,
          10 gallons of oil is a BIG top up!
          Keep in mind there are the final drives are separate from the transmission oil.
          You need to get under the machine & pull the oil level/filler plugs on each side to check them.
          Re testing the transmission charge pump, it needs to be done with a flow meter.
          That’s a bit of a voodoo word, as not too many repairers seem to own one…
          You could start by checking the system pressure with a test gauge & see if there is any pressure at all.
          If the machine has sat for a long time, it may be worth pulling the suction hoses to the transmission charge pump & make certain they haven’t perished internally & caused a restriction.

          Hope this helps

  • Alrman:
    What a great site! I am so glad there are communities like this willing to share information.
    My friend has a 1984 Case 850E Long track dozer set up for skidding trees that he has recently bought. Although they claim the final drives where serviced, the right final drive is leaking fluid around the bottom pan seal. When you pull the level plug, there is pressure that releases from the plug. The left side final drive does not do this. I assume the leak is coming from the excess pressure, but I am not sure where the pressure is coming from. From what I have read, the final drives and transmission are separate cavities so the pressure would have to be coming from the final drive case itself. Any insight on this would be greatly appreciated.

    • Hello Chris,
      It is common to have some pressure in the final drive compartments.
      As operating temperatures rise the oil expands a little & without a compartment breather, a little bit of pressure is present – as is a little vacuum when the compartment is stone cold.
      As to the difference between the two compartments, my guess is that there maybe a seal problem with the bevel/bull pinion shaft or maybe even the duo cone seal at the axle shaft – this would leak externally behind the track sprocket.
      My suggestion is to address the leak you have by draining the final drive, removing the lower cover, thoroughly cleaning the mating surfaces & resealing using Loctite 515 & using threadlock on the bolts as well.
      Then monitoring closely the oil levels on both sides to see if there is difference in oil levels over time.
      If either side has an issue with the bevel/bull pinion shaft seal, (upper shaft) oil from the transmission will likely be entering that final drive – raising the level.
      It wouldn’t hurt to clean the porous transmission breather in the filler tube & be sure the second breather hose from the top of transmission housing to the fluid recovery bottle (located under right armrest) is not damaged or blocked in some way.

      A great community for help with questions/information re any earthmoving equipment is I am one of the regular contributors there.


      • I will advise my friend. We will check fluid and report back when we find some new information

  • I have a case 350 and just recently all the sudden it quit moving both directions. The only way it will move is by holding either cutting clutch and it will move in either direction. It turns left or right just barely while holding the clutch also. Any ideas it’s got over a 100 hours since I had the toque rebuilt with a new pump put in it.

    • Hi Matthew,
      It would seem there maybe a problem in the shuttle.
      Is the oil level being checked at an idle?
      By saying the torque was rebuilt – Does that mean the power shuttle overhauled as well?
      Sometimes when a problem like this arises, the first place to look is the last place worked on……

      Sorry I can’t be more specific

      • It was overhauled a while back. They rebuilt the same thing 15 years ago with no problems. It seems to have plenty of power when clutch is held.
        I was wanting what to look for in the rearend. It’s the only thing on this machine I have never been in.

        • When you are saying “When clutch is held” – I am assuming it’s the steering control levers between your legs?
          If so, they work as brakes for each side, so I am having a hard time figuring exactly what you are describing.
          If it’s a pedal, I can only recall a brake pedal – that applies both LH & RH steering brakes at same time?
          The oil level at the shuttle is correct? Checked at engine idle?

  • Hello Alrman,

    Case 850D. I put new LED, 24vdc lights on the corners of the rops to replace the old bad lights. When i turn the lights on, they stay on for about 5-10 seconds and then it kills the entire machine. Shut light switch off, fire machine right back up with no problems. It’s odd, almost like slow blow fuse. Any thoughts where to start?

    • Hello Brian,
      You will find a circuit breaker controlling the entire accessory function behind the dash.
      You obviously have a short to ground somewhere in the light circuit – trying to locate the fault will involve carefully inspecting & jiggling the wiring loom going from the switch to each light.
      On an older model that has not had the lights functioning for some time, the fault could be anywhere.
      Sometimes it’s just simpler to run new wires.

      Sorry I couldn’t be more specific

    • I have an older model Case 450B crawler. Ive been using this machine on my ranch for about 24 years clearing fence rows. The machine started making an intermittent popping on the left side. I initially thought this was from the final drive. I removed this and found no issues. I reassembled the final drive and within 5 minutes the intermittent popping was back. Im leaning towards a bad bearing on the bevel pinion shaft (terms from my parts book) or on the high/low shaft. I haven’t checked the fluids yet for signs of the problem. Im by no means a master mechanic but tend to be able to fix most of what I get into. Do you have an opinion? If this is a bearing can it be changed with the transmission in the machine? Thank you!

      • G’day Matt,
        I’m assuming the final drive was removed from the machine & dismantled – to find no issues?
        If the pinion shaft bearing/s are an issue – I would remove the transmission to do the repair, simply because of the lack of space to try to do such a repair with it still in the machine.
        However if the pinion shaft bearing is at fault, I would think there would be signs of such a failure in the oil drain tin or the suction screen.

        Be absolutely certain the track rollers & idler bearings are in good order by checking for any movement with a prybar.

        Good luck!

        • Hello, back again with a follow up question. I started working on this machine. I removed the transmission brake from the front on the left side believing this may be where the issue is. I did find the front pinion bearing cage was very loose. I was trying to remove this bearing and the roller cage came apart. I gave accounted for all the rollers. My next problem is it appears this bearing is pressed on the shaft. I cannot get the inner cone/race of the bearing off the shaft. Looking for any ideas to remove this. I am working on this in the machine. My next step was going to be to remove the right transmission brake and the front of the transmission for more room. Im doing what I can not to remove the tracks, final drives and entire transmission. Thanks in advance!

          • Hello Again Matt,
            How are your ribs feeling? 😉
            If the bearing was at fault for the popping noise, I would think the rollers would be damaged or destroyed?
            To get that pressed on race off the shaft – you are going to have to get creative.
            Heat will need to be applied OR the race be ground thin & cracked or broken – each could allow contaminates into the transmission.
            Possibly, if there is enough access, you could weld 2 x pieces of 10mm threaded rod to the race, opposite to each other, so they extend past the end of the shaft, & fabricate a plate with 2 x holes to suit & use it as a puller.
            Be careful with where the slag & sparks end up & not set the machine on fire!


  • Hi Alrman,
    Thanks for the response on the lights. Another question, after running the machine hard for hours in about 80 degrees Fahrenheit weather, the water temp gets right on the edge of hot (red on dash), and the converter temp is hot as well (bonces right on red/yellow line). i’ll spray down the radiator, and engine temp comes down quickly. Is there a radiator for the transmission that perhaps is dirty, or are these units known for running hot?

    • Hey Brian!
      No machines are really built to run hot.
      First thing I check in this situation is air flow through the radiator/oil cooler. Many operators have been fooled to think the core is clear by what they can see from the outside of the machine.
      At full RPM it should be quite uncomfortable to stand in front of the machine because of the amount of air flow it should create.

      TIP – never hose down a radiator & then go & move dirt while it is still wet – the fan pushes the dirt/dust into the wet core & plugs it up.

      I would recommend removing the radiator/oil cooler & the shroud – giving them a thorough pressure clean & blow dry with air – then refit.
      You could try to do this without removing the radiator, but you can’t really get to the corners of the core with the shroud still fitted.

      Depending on the dust situation your working in, regularly maintain the radiator by back blowing out the core at the end of the day with compressed air or even a good leaf blower.

      Without seeing your machine, this is only a guess, but it’s an educated guess 😉


      • On the 850D: Does transmission oil have a radiator like the hydraulic oil does? Is the hydraulic oil and transmission oil the same reservoir?

        • The oil cooler next to the engine radiator is for the transmission oil. There is no hydraulic oil cooler.
          The reservoir question concerns me a little… I thought you already knew the dipstick next to the batteries at the rear door acted as a transmission oil filler as well.

  • Hello Alrman, you were exactly right on the radiator, looks good from the outside, inside was plugged.

    Do you have any experience with excavators? Specifically a Komatsu PC200-6? I’m having issues where the swing function completely stops after a few seconds UNLESS you’re using another function (boom, crowd or curl) simultaneously. It’s odd, almost as if the swing lock engages. I’m afraid it’s going to rip the ring gear right out of the house. As always, thanks for the help


    • Hey mate, good that your on to sorting the dozer.
      Case gurus don’t have time to learn about Komatsu excavators.
      It would seem there could be an issue with pilot control pressure , either in supply or swing circuit, but don’t take my word on that……

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